The global bond market is flashing another warning sign.
US Treasury yields have climbed sharply, with the 30-year yield around 5.27%, close to its highest level since 2007. The rise is pushing up borrowing costs for households and companies while adding pressure to stock valuations.
And now, Japan is becoming an important part of the story.
Japan is the largest foreign holder of US Treasurys, with roughly $1.1 trillion in holdings. For years, Japanese investors looked overseas because interest rates at home were extremely low. That is changing quickly.
Why rising Japanese rates matter
Japan’s 10-year government bond yield has reached around 3%, its highest level since 1996.
That changes the investment equation for Japanese institutions and savers.
When Japanese bonds offered very low returns, investors had a strong reason to look abroad for better yields. US Treasurys were one of the major destinations.
Now, with Japanese government bonds offering more attractive returns, some of that money could move back home.
That would mean less demand for US government debt, at a time when the Treasury market is already dealing with elevated yields and heavy supply.
The bigger risk: yen intervention
There is another link between Japan and the US bond market.
A weak yen can push Japanese authorities to buy yen using dollars. If Japan needs to raise those dollars by selling Treasurys, that could put additional pressure on US bonds.
That is particularly important because bond prices and yields move in opposite directions.
More Treasury selling can push prices lower, which means yields move higher.
And higher long-term yields can feed into:
- Mortgage rates
- Corporate borrowing costs
- Stock valuations
- Government financing costs
So a problem that starts in Japan can quickly become a problem for US markets.
Japan has already been selling Treasurys
There are signs that Japanese investors have reduced their Treasury exposure.
Japan-based investors sold a net $71 billion of US government debt through June.
But the details matter.
Around $69 billion of those sales came from short-term Treasury bills, which mature within one year.
Sales of longer-term Treasury notes and bonds were only around $3 billion.
That distinction is important because long-term Treasury yields have a much bigger impact on mortgages, corporate borrowing costs and equity valuations.
So far, the feared large-scale dumping of long-term US debt has not happened.
The Fed has a tool that could help
This is where the Federal Reserve’s FIMA repo facility comes into the picture.
The facility allows foreign central banks to temporarily exchange US Treasurys with the Fed for dollars instead of selling those Treasurys directly into the market.
For Japan, that could be useful during periods of currency intervention.
Rather than selling Treasurys to raise dollars for yen purchases, Japan could use the facility to obtain the dollars while temporarily pledging its Treasury holdings.
That could reduce the immediate selling pressure on US bonds.
The US and Japan jointly intervened to support the yen on July 31, and Japan later indicated that it planned to use FIMA in the future.
Treasury Secretary Scott Bessent has also urged the Fed to consider increasing the facility’s capacity.
But there is an important limitation.
FIMA can reduce forced Treasury selling. It cannot change the fact that Japanese investors may find domestic bonds more attractive.
US yields are approaching a key level
The US 10-year Treasury yield has climbed to around 4.8%, while the 30-year yield has moved to roughly 5.26%.
For investors, the level is only part of the story. The speed of the move matters too.
A gradual rise in yields can be absorbed by markets.
A rapid rise can create much more stress, especially if it reflects forced selling, weakening liquidity or investors unwinding leveraged positions.
Some analysts believe 5% on the 10-year Treasury yield could become an important psychological threshold.
A sustained move above that level could create a more defensive environment across financial markets.
This is not a crisis yet
Despite the warning signs, the market has not reached crisis territory.
Liquidity in the US Treasury market remains broadly stable, and there are currently no clear signs of the kind of market dysfunction seen during the 2022 UK debt crisis.
That distinction matters.
The concern is not simply that yields are high. The bigger risk would be a disorderly and rapid rise in yields.
If investors begin aggressively selling bonds, liquidity deteriorates and leveraged positions are forced to unwind, the pressure could spread across markets.
Why stocks should care
Higher bond yields make the competition for investors’ money tougher.
When government bonds offer higher returns, investors have more reason to demand attractive valuations from stocks.
Higher yields also raise companies’ financing costs and reduce the present value of future earnings, which can weigh particularly heavily on growth and technology stocks.
For now, strong corporate earnings are helping stocks absorb the pressure. But if Treasury yields continue climbing, the bond market could become a much bigger factor in equity valuations.
The global bond selloff is bigger than the US
The pressure is not limited to Treasurys.
Long-term yields have also moved higher across major markets.
- Japan’s 30-year bond yield has reached a record high
- UK 10-year gilt yields have climbed to their highest level since 2008
- German 10-year bund yields recently reached their highest level since 2011
The common thread is growing concern around inflation, government borrowing and fiscal pressure.
The US remains at the center of the story, but global bond markets are increasingly moving together.
What investors should watch next
The key question is whether the bond selloff remains orderly or turns into something more disruptive.
Three things deserve close attention:
1. The US 10-year yield
A sustained move above 5% would put a major psychological level in focus.
2. Japan’s policy
Markets are watching whether the Bank of Japan raises rates and whether Japanese investors start moving more money back into domestic bonds.
3. Treasury market liquidity
If liquidity deteriorates or forced selling begins to appear, the situation could become much more serious.
For now, the bond market is under pressure, but it is not in crisis.
The bigger concern is what happens if high US yields, rising Japanese rates, yen weakness and global fiscal pressures start reinforcing each other.
That is the scenario policymakers are trying to prevent before it becomes a much bigger problem.